Figure 6.
A, Picroliv potentiates TNF-induced apoptosis in KBM-5 cells as determined by TUNEL and Annexin V assay. Cells (1 × 106/mL) were pretreated with 150 μg/mL picroliv for 12 h and then incubated with 1 nM TNF for 24 h. The cells were then stained for TUNEL positivity or incubated with a fluorescein isothiocyanate-conjugated Annexin V antibody and analyzed using flow cytometry. B, Live/Dead assay results indicating that picroliv upregulates TNF-induced cytotoxicity. KBM-5 cells were preincubated with 150 μg/mL picroliv for 12 h and then treated with 1 nM TNF for 24 h. Cells were stained with Live/Dead assay reagent for 30 min and then analyzed under a fluorescence microscope. C, Picroliv potentiates TNF-induced apoptosis as determined by PARP assay. KBM-5 cells were preincubated with 150 μg/mL picroliv for 12 h and then treated with 1 nM TNF for the indicated times. Whole-cell extracts of the cells were prepared, subjected to SDS-PAGE, and blotted with an anti-PARP antibody. D, Picroliv suppresses TNF-induced invasion. H1299 cells were seeded in a Matrigel invasion chamber overnight in the absence of serum, co-incubated with 150 μg/mL picroliv and 1 nM TNF for 24 h in the presence of 1% serum, and then subjected to an invasion assay as described in Materials and Methods.